Upon fine crushing of hard material, e.g. stone blocks or ore blocks, material is crushed that has an initial size of approx. 100 mm or less to a size of typically approx. 0-25 mm. Crushing, e.g. fine crushing, is frequently carried out by means of a gyratory crusher. Known crushers have an outer shell that is mounted in a stand. An inner shell is fastened on a crushing head. The inner and outer shells are usually cast in manganese steel, which is strain hardening, i.e. the steel gets an increased hardness when it is exposed to mechanical action. A known gyratory crusher has a driving device for crushing the material between the inner and outer shells in a known way.
However, about 125 years have passed since the first gyratorycrusher was created, and such crushers are now used almost everywhere in the world, but its basic design has not changed. Hence, if the crushing force in a gyratorycrusher is to be increased, e.g. by 20% to improve the crushing capacity, the crusher designers have hitherto conventionally only “upscaled” the crusher, i.e. most of the dimensions of a smaller crusher has been increased in an enlarged scale being proportional to the increased crushing force to be able to carry and withstand the increased crushing force. This enlargement of known crushers increases both their own/tare weight and their outer dimensions in proportion to the increased crushing force. This is shown in FIGS. 1 to 6 where increasing crusher capacities and crushing forces requires the conventional enlarging of the crushers “all-over” in proportion to the increased crusher force from the smallest crusher in FIG. 1 to the largest crusher in FIG. 6.